Control valve



Jan. 21, 1941. J. w. MARTIN CONTROL VALVE Filed Sept. 29, 1938 w ZZZ/ Mi A'ITGNEY.

Patented Jan. '21, 1941 UNITED. STATES- PATENT .TOFFICE' CONTROL VALVE James Woodward Martin, Dallas, Tex. Application September 29, 1938, Serial No. 232,415

' 4 Claims. (01. '137 1'53) This invention relates to control valves of a type-which automatically control the flow of a fluid used to control the temperature or pressure of some object or medium. Valves of. this type are usually provided with an expansible chamber actuated by slight variations-in pressure within said chamber. The expansible chamber is associated with a. suitablevalve in such a manner that actuation of the expansible chamber oper'ates the'valve, thereby controlling the flow 'of fluid through the valve. Control valves are usually constructed so that in case theexpansible chamber ruptures, the fluid inside said chamber is permitted to pass into the valve chamber, or fluidfrom the valve'chamber permitted to pass into the expansible chamber, or the fluid from the expansible chamber permitted to escape into the atmosphere, at the location of the control valve. Also, in case the valve chamber diaphragm, bellows, or packing ruptures or leaks, the fluid from the valve chamber is likewise allowedv to escape into the atmosphere at the location of the control valve. In many instances, such conditions are not only undesirable but actually dangerous.-

It is, therefore, the principal object of 'this invention to provide a safe, simply constructed control valve so constructed and operable that it controls the flow of a fluid used to control the temperature or pressure of some object or medium,

the valve having an arrangement of parts whereby in case either the expansible chamber bellows or the valve chamber diaphragm ruptures, the escaping fluid will be'conducted through a single vent to a predetermined and safe location.

It is also an object of this invention to restrict the expansible chamber inlet so that in case said; expansible chamber bellows ruptures, the quantity of escaping fluid is reduced to a minimum. The restricted inlet is of such area with respect to the vent opening as to prevent appreciable increase in pressure in the vent chamber in case of rupture of said expansible chamber bellows.

, Other and further objects of the invention will become apparent from a perusal-of the following detailed description, taken in connection with the accompanying drawing, and wherein a preferred form of embodiment of the improved valve is clearly shown. The drawing illustrates a form of my invention especially adapted to the control of pressure within a vessel by controlling-the feed of fuel gas to a burner, but the drawing is only for the purpose of illustrating an example of the operation and adaptability of the control valve.

In the drawing:

' nozzle 21 is a part of the valve body I Fi ure 1 is a side elevational view of the control valve; Figure 2 is a partly sectioned and somewhat enlarged detail view showing the valve disc, disc nipple and'disc retaining sleeve; and 5 Figure 3 is a vertical sectional view taken through the view shownin Figure 1. a

In carrying out the invention, there is provided a housing consisting of the valve body I, the base 10, and the center fltting 8. The valve and extends 23. Avalve disc disc nipple 5 by 28. A spring 2 into a valve chamber shown at 4 is held in position against a means of a disc-retaining sleeve tends to open or hold the valve open and'opposes 1d the action of an expansible chamber indicated at I6. The fluid in the valve chamber 23 is separated from the fluid in the expansible chamber l6 by a valve chamber diaphragm or bellows 2|, the vent chamber, shown at of the expansible chamber, I 6. The'vent chamber is open to the atmosphere and the discharge therefrom is piped to a predetermined safe point. The expansible chamber I6 is held securely in proper position by a lock nut is. The flexible 25 diaphragm or bellows 2| eliminates the necessity of providing a packing gland in order to transmit the movement of the expansible chamber It to the disc nipple 5 and the valve disc 4. The con-' struction of this device makes it possible to assemble the complete valve parts and test the valve,

diaphragm lock nut washer 8, diaphragm lock nut 1, center fitting 8, lock screw 20, inlet fitting 24, inlet screen 25, and outlet fitting 26. The 40 construction of the base III, center fltting 8, ex-

pansible chamber 9, expansible chamber nipple l4, and lock nut l3 permit the. assembling of these parts after the valve assembly has been properly tested. The expansible chamber nipple l4 contains a passageway l6a through the entire nipple-one end of which terminates within the expansible chamber IS, the other end of which is restricted as shown at H to permit passage of a very small amount of fluid. The novel feature of this restriction is one of the objects of the invention. v v

The operation of the valve is as follows: slight variations in the controlled pressure, which is introduced into the expansible chamber I 6 through l8, and the wall 9 20 I her nipple II by means ling fluid passing throughthe valve.

the restricted duct or inlet iii in the nipple ll, cause the bellows to expand as the pressure increases, thus overcoming the force oi. the spring 2, and thereby moving the valve disc 4 toward the face of the valve nozzle 21, reducing the annular space 3 which retards the fiow of control- Likewise. when the pressure is reduced in the expansible chamber it, the force of the spring 2 causes the valve disc 4 to move away from the lace oi the valve nozzle 21, thereby increasing the annular space 3 which increases the flow of controlling fluid passing through the valve. The controlling fluid enters the valve chamber 23 through the passageway 24a in the inlet fitting 24, passing through inlet screen 25, then (when the valve is open) the fiuid passes through the ports 22 in the disc retaining sleeve 28 and between the valve nozzle '21 and the sleeve 28, through valve nozzle passageway 21a and outlet fitting passageway 26a to the bumen The vent chamber l8 separates the valve chamber 23 from the expansible cham-' her it, and also maintains atmospheric pressure on the outside face of valve chamber diaphragm 2i and the outside suriaceoi the expansible chamber e. Vent fitting l'l, attachedto the base it, provides a'means for conducting vent through vent fitting passageway lid to a predetermined safe point away from the location or the valve.

Where the temperature of some object or medium is to be controlled, the actuating pressure within the expansible chamber i6 is obtained by means of a conventional thermostatic bulb located at the point where the temperature is to be controlled and connected to the expansible chamof tubing-thermostatic bulb, tubing, and expansible chamber to be filled I with proper fluid and hermetically sealed.

practical work While the'disclosure reveals a ing embodiment of the invention, it is to be understood that changes, alterations and modifications may be made therein, in keeping with the spirit thereof, and which may be said to fall fairly within the scope and meaning of the ap-.

pended claims.

What is claimed as new is:

1.- In a device of the character described, the combination of a valve assembly, a valve body having inlet and outlet passageways; a' base, means torconnecting the valve body to the base;

said valve body providing a valve chamber; said base providing a vent chamber, a vent therefor;

. an element constituting an expansible chamber valve chamber in line with carried in said' vent chamber;

ble chamber and in said valve assembly;

, a valve chamber diaphragm operably associated-with the expansia valve and disposed in the said valve assembly; an opening in said base, an expanslble chamber nozzle having a. passageway nipple in said opening, said nipple having a re- ,stricted passageway to permit entrance of a suitable medium under slight variations of pressure to actuate said expansible chamber, the valve chamber diaphragm and the valve assembly in the opening and closing thereoLin the manner and for the purposes described.

2. In a device of the character described, the combination of a valve assembly, a valve body having inlet and outlet passageways; a base, means for connecting the valve body to the base; said valve body providing a. valve chamber, Said base providing a vent chamber with a single vent; an element constituting an expansible chamber carried in said vlent chamber, a valve chamber bellows operably associated with the expansible chamber, a valve nozzle having a passageway and disposed in the valve chamber in line with said valve assembly; said valve assembly consisting of a diaphragm, a perforated diskretaining sleeve, a valve disk, a disk nipple, a spring, and means for holding the parts together; an opening in said base, an expansible chamber nipple inthe opening, said nipple having a predetermined restricted passageway to permit outside or extraneous pressure under variations of a foreign medium to actuate said expansible element and the valve chamber bellows and its valve parts I in the opening and closing of the valve; said nipple having said restricted passageway of a size in proper relation to the size of the single vent passageway to prevent increase of pressure in said vent chamber and to reduce the volume of escaping fluid in case of rupture of the expansible a diaphragm operably associated with the expansible chamber and forming part or the valve as- Y sembly; a'valve nozzle having a passageway and disposed in the valve chamber in line with said valve assembly; an opening in said base, an expansible chamber nipple in the opening, said nipple having a restricted passageway to permit remote pressure under slight variations of a suitable element to actuate said expansible chamber, diaphragm and valve assembly in the opening and closing thereof.

4. A device of the character described such as defined and'as claimed in claim 3, and wherein said base provides a vent chamber having a single vent for the purpose of conducting escaping fluid either from the vent chamber in case of rupture of the expansible chamber wall, or the valve chamber in case of rupture of the valve chamber diaphragm, or from both said chambers in case the expansible chamber wall and valve chamber diaphragm rupture simultaneously.

- JAMES WOODWARD MARTIN. 

